Understanding the behaviour of a niobium oxide cathode in a molten chloride bath using different DC voltammetric techniques

The electro-deoxidation of metal oxides has been presented as an alternative to the pyro- and electro-metallurgical techniques generally used create metals alloys. However, previous research concentrated on employing chronoamperometric analyse cathodic reactions, ignoring important information reduction processes. In this work, we examine using several DC voltammetric techniques, including constant potential chronoamperometry, sampled-current voltammetry, linear sweep current chronopotentiometry. Niobium pentoxide was taken model cathode material. As a result, following mechanism is proposed: (1) Nb (V) oxidation state, represented by compounds Nb2O5, CaNbO6, Ca2Nb2O7, reduced (IV) in NbO2 CaNbO3; (2) (III) form CaNb2O4; (3) CaNb2O4 quickly NbO, which only Nb(II); latter Nb(0) end process. results show that NbO partially dissolves electrolyte suggest creation two distinct soluble niobium complexes, depending oxygen level electrolyte.